document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1086473>Question 1086473</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1)Lisa drove 60 miles, then increased her speed by 15 miles per hour for 135 miles. If the second part of the drive took 1 hour longer than the first part, find her average speed.<BR>\n" );
document.write( " What I have so far:    240/(s-20)    -60/s the whole eq multiplied by s(s-20) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #700720 by </B><A HREF=/tutors/aboutme.mpl?userid=jorel1380><B>jorel1380(3719)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jorel1380><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=jorel1380><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=700720\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let n-15 be Lisa's first speed, and n be her second speed. Then:<BR>\n" );
document.write( "60/(n-15) +1=135/n<BR>\n" );
document.write( "60n+n²-15n=135(n-15)<BR>\n" );
document.write( "n²-90n+2025=0<BR>\n" );
document.write( "(n-45)²=0<BR>\n" );
document.write( "n=45<BR>\n" );
document.write( "n-15=30<BR>\n" );
document.write( "60/30=2<BR>\n" );
document.write( "135/45=<BR>\n" );
document.write( "135+60 miles/2+3 hours=39 mph avg<BR>\n" );
document.write( "&#9786;&#9786;&#9786;&#9786; </SPAN>\n" );
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